Add Stimulus controller to launch format popup

app/assets/stylesheets/_utilities.scss

@@ -6,6 +6,10 @@
   font-size: 10em;
 }
 
+.fs-7 {
+  font-size: .8rem;
+}
+
 .pe-none {
   pointer-events: none;
 }

app/assets/stylesheets/application.sass.scss

@@ -80,6 +80,7 @@ $unicodeRangeValues in Lexend.$unicodeMap {
 "overrides/minicolors",
 "overrides/modal",
 "overrides/navbar",
+"overrides/popover",
 "overrides/turbolinks",
 "overrides/toasts",
 "overrides/sweet-alert";

app/assets/stylesheets/overrides/_popover.scss

@@ -0,0 +1,13 @@
+.popover {
+  box-shadow: $box-shadow-sm;
+  background-color: var(--raised-bg);
+}
+
+.rs-popover {
+  --popover-arrow-border: transparent;
+  --popover-border-color: transparent;
+}
+
+.popover-body p:last-child {
+  margin-bottom: 0;
+}

app/javascript/retrospring/controllers/format_popup_controller.ts

@@ -0,0 +1,18 @@
+import { Controller } from '@hotwired/stimulus';
+import { Popover } from 'bootstrap';
+
+export default class extends Controller {
+  connect(): void {
+    const formatOptionsElement = document.getElementById('formatting-options');
+
+    this.element.addEventListener('click', e => e.preventDefault());
+
+    new Popover(this.element, {
+      html: true,
+      content: formatOptionsElement.innerHTML,
+      placement: 'bottom',
+      trigger: 'focus',
+      customClass: 'rs-popover'
+    })
+  }
+}

app/javascript/retrospring/initializers/stimulus.ts

@@ -2,6 +2,7 @@ import { Application } from "@hotwired/stimulus";
 import AnnouncementController from "retrospring/controllers/announcement_controller";
 import AutofocusController from "retrospring/controllers/autofocus_controller";
 import CharacterCountController from "retrospring/controllers/character_count_controller";
+import FormatPopupController from "retrospring/controllers/format_popup_controller";
 
 /**
  * This module sets up Stimulus and our controllers
@@ -15,4 +16,5 @@ export default function (): void {
   window['Stimulus'].register('announcement', AnnouncementController);
   window['Stimulus'].register('autofocus', AutofocusController);
   window['Stimulus'].register('character-count', CharacterCountController);
+  window['Stimulus'].register('format-popup', FormatPopupController);
 }